Christians have expressed their support for a Girl Guide unit in Harrogate that has vowed to retain the original religious Promise.

Girlguiding UK voted earlier in the year to change the Promise to "love my God" to instead "be true to myself and develop my beliefs". Although the Promise to serve the Queen remains unchanged, new guides will no longer promise to serve "my country" but rather "my community".

The leader of the St Paul's Harrogate unit, Hazel Mitford, told volunteer leader Jem Henderson in a letter that it would be "sticking with the previous Promise".

However, 28-year-old Jem Henderson, has complained that the stance is unfair to her and other atheists in the unit.

Henderson was quoted by The Times as saying that the decision "excludes me and any other atheist girls from the troop, or asks us to lie when making the Promise, something that surely goes against the principles of the Guides".

In a letter to The Times, Premier Christian Media chief executive Peter Kerridge said the decision to do away with the original Promise was "unfair and illogical".

"Christians throughout Britain should applaud St Paul's Girl Guides in Harrogate for standing up for their beliefs and retaining the Girl Guide promise to 'love my God' in the face of on-going secular pressure," he said.

The traditional Promise has been in place since 1910 but will be replaced by the new secular version on September 1.

Mr Kerridge continued: "This sorry scenario represents yet another attack on Christianity in a Christian country by an increasingly militant Secular element, intent on erasing God and Christ from society.

"Christianity is a way of life and the corner stone of many of our respected institutions – including the Scout movement and Girl Guides.

"It welcomes everyone and anyone as brothers and sisters in the eyes of God but must not submit to pressure to dilute or delete its fundamental principles."

The former Bishop of Rochester, Michael Nazir-Ali, was quoted by The Telegraph as saying that he hoped "many others" would adopt a similar stance to the Harrogate unit, which meets in St Paul's United Reformed Church.

Girlguiding UK said in June that it was changing the promise to "reach out to girls and women who might not have considered guiding before so that even more girls can benefit from everything guiding can offer".

St Paul's pack leader Mrs Mitford was among the signatories of a letter sent to the Harrogate Advertiser after the announcement expressing "dismay" at the change.

"You would not join the Lawn Tennis Association and insist they had to make provision for all other sports. Girlguiding has God at its core and anyone who has issue with this is free to start their own organisation," the letter stated.

It added that anyone who felt unable to make the religious Promise could make the new one instead.